The F-35's helmet displays an augmented reality overview, which is drawn from six cameras across the body of the plane. This enables the pilot to look around the cockpit and, instead of seeing the interior of the plane, see directly through the cameras at the world outside.

This computational capability is all run by a computer system called ALIS.

David Martin, a correspondent for 60 Minutes, reports that ALIS (emphasis ours):

... Looks basically like a laptop computer, and the pilot carries it out to the plane and sticks it in a slot right next to him in the cockpit. That contains all the information about the mission he's gonna fly. The servers which run all of this software take up a room about the size of a shipping container.

This is a juicy, juicy target for a hacker. If your adversary can hack into all that software that's running [the mission], then they've essentially defeated the plane. All without firing a bullet.

So it seems the ALIS has been given too much power over the F-35. For example, ALIS has the ability to ground planes indefinitely if it detects anything wrong with the plane. Human intervention cannot overrule ALIS, either.

If hackers could manage to infiltrate the network that ALIS relies on, it is very possible that they could brick an entire F-35 fleet. This would render the plane, the most expensive weapons system ever, completely useless.